Review board reveals findings on Climate Orbiter

Wide-ranging managerial and technical actions are underway at JPL in response to the loss of the Mars Climate Orbiter and the initial findings of NASA's mission failure investigation board, whose first report was released Nov. 10.

Focused on the upcoming landing of the Mars Polar Lander on Dec. 3, JPL's actions include: a newly assigned senior management leader, freshly reviewed and augmented work plans, detailed fault tree analyses for pending mission events, daily teleconferences to evaluate technical progress and plans work yet to be done, increased availability of the Deep Space Network for communica-tions with the spacecraft, and independent peer review of all operational and contingency procedures.

"The board recognizes that mistakes occur on spacecraft projects," the NASA report said. "However, sufficient processes are usually in place on projects to catch these mistakes before they become critical to mission success. Unfortunately for Climate Orbiter, the root cause was not caught by the processes in place in the Climate Orbiter project."

"We have mobilized the very best talent at JPL to respond thoroughly to the specific recommendations in the board's report and the other areas of concern highlighted by the board," said JPL Director Dr. Edward Stone. Tom Gavin has been temporarily reassigned as full-time program manager for Mars Polar Lander. Other temporary senior management assignments for Polar Lander are Dr. Richard Zurek, project scientist; Richard Cook, project manager; and Matt Landano, deputy project manager.

"Special attention is being directed at navigation and propulsion issues, and a fully independent 'red team' will review and approve the closure of all subsequent actions," Stone added. "We are committed to doing whatever it takes to maximize the prospects for a successful landing on Mars on Dec. 3."

To that end, Stone pledged that JPL will take actions on several fronts:

• Navigation: direct interaction will take place between the spacecraft team and collocated navigation team member; additional navigation techniques will be employed; and trajectory correction manuever no. 5 will be baselined.

• Systems engineering: a chief systems engineer has been assigned for Polar Lander; a formalized operational requirements verification metrix has been formed, as has a comprehensive fault tree of entry, descent and landing.

• Engineering: significantly increased temperature margin of the propulsion system during descent and landing, and a reverified propulsion system operation.

• Peer review: 30 JPL principal engineers will provide an intensive review of Polar Lander's entry, descent and landing; six senior Lab navigators will comprise an advisory group and peer review team; plan items; and the size of the Polar Lander review board has been doubled.

• Mission safety: a senior mission assurance manager has been assigned; all prior risk assessments and software and interfaces are being revalidated.

The NASA board's report identifies eight contributing factors that led directly or indirectly to the loss of the orbiter. These contributing causes include inadequate consideration of the entire mission and its post-launch operation as a total system, inconsistent communications and training within the project, and lack of complete end-to-end verification of navigation software and related computer models.

"The 'root cause' of the loss of the spacecraft was the failed translation of English units into metric units in a segment of ground-based, navigation-related mission software, as NASA has previously announced," said Arthur Stephenson, chairman of the Mars Climate Orbiter Mission Failure Investigation Board and director of NASA's Marshall Space Flight Center, Huntsville, Ala. "The failure review board has identified other significant factors that allowed this error to be born, and then let it linger and propagate to the point where it resulted in a major error in our understanding of the spacecraft's path as it approached Mars," Stephenson added.

At a Nov. 10 briefing on the board's findings, Dr. Ed Weiler, NASA's associate administrator for space science, was asked if anyone at JPL should lose their job over the loss of the mission. "Who would I replace them with?," Weiler replied. "These are the best people in the world. Nobody does it better than JPL; they've done it for 40 years, and they've done the impossible. Mars Pathfinder was a 'faster, better, cheaper' mission, and it was 10 times cheaper than Viking. But the whole philosophy of 'faster, better, cheaper' includes following the rules and processes in place."

The board's report is available online at ftp://ftp.hq.nasa.gov/pub/ pao/ reports/1999/MCO_report.pdf. Stone's presentation at the Nov. 10 briefing is available at ftp://ftp.hq.nasa.gov/pub/pao/reports/1999/ MCO_charts.pdf. JPLers watch Nov. 10 briefing on the findings and recommendations of the NASA Mars Climate Orbiter investigation board.

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